Electronic data is typically represented using a binary number system. The binary number system is one in which values may take on one of two states, typically represented by a “1” and a “0”. Various types of memory systems have been developed which include small programmable devices that store a single bit as either a “0” or a “1”. For example, a transistor may be used as a switch which is either in an ON state or an OFF state. The ON state may be used to represent a “1” while the OFF state may be used to represent a “0”.
One type of memory architecture being developed is crossbar memory architecture. Crossbar architecture includes two sets of interconnecting wire segments. A programmable device may be placed at each crosspoint between each wire segment. In one example, crossbar architecture may employ memristors as programmable devices. A memristor is a resistor which is able to change the value of its resistance in response to various programming conditions. A memristor may represent a “1” while in a low resistance state and a “0” while in a high resistance state.
When memristive devices are placed in crossbar architecture, it may be desirable to limit the number of memristive devices in a low resistive state along a particular wire segment of the crossbar architecture. Having too many devices in a low resistive state along a particular wire segment may allow too much electric current to pass through. Too much electric current passing through the wire segments may potentially interfere with read/write operations.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.